Effects of organizational structure on performance of refractory materials

Influence of refractory materials under various physical, chemical reactions at hightemperature in the process of using the occurrence of corrosion, wear, or split and cause damage. Therefore, refractory material must have the ability to adapt to various working conditions, and the performance and composition and structure is closely related to the.

Chemical composition is the basic characteristics of refractory materials; the main component is the basic feature ofrefractory material, so the composition and quantity directly determines the performance of refractory materials. Refractory products at the same time, mineral composition, product properties are the comprehensive reflection of minerals and micro structure, and therefore cannot only from the chemical composition analysis of the effect on the properties of products. The refractory material of mineral composition and depends on the chemical composition and process conditions. Although the same chemical composition. If the different processing conditions. The crystalline phase and the number of mineral species will also have the difference, the different properties of refractory materials. However, it must be stressed that refractory material macro organizationalstructure is an important factor which influences the performance, and performance index and can reflect the internal structure ofrefractories. For example: – densification properties of porosity, density, true density body Zhi said gas permeation properties of the ease of permeability: properties thermal properties of linear expansion coefficient, thermal conductivity, heat capacity and thermal conductivity; representation properties mechanical properties and high temperature strength, high temperature often pits, bending strength high temperature tensional strength, high temperature creep and elastic modulus; as, refractoriness, refractoriness under load, high temperature and volume stability, thermal shock resistance and slag resistance of high temperature performance.

Therefore, the use of departments must be from the characteristics and process of thermal equipment requirements, carefully selected according to the chemical composition, mineral structure, refractory material and macro microstructure and performance indicators, in order to achieve the desired effect

Correct using method make refractories have anti damage ability

Supporting the development of refractories for the clinker rotary kiln each work with the different mining conditions, targeted to different anti damage of refractory materials, andconsidering the basic matching problem with various working lining life, reduce maintenance times to stop the kiln, each work with lining, the anti damage of independent and phase the purpose of matching cycle. Lining material preheating with good chemical stability, alkali erosion leaf wax stone brick and strong, the pyrophyllite using low alkali and high alkali bricks siliceous raw material, the raw material made of, whether or not to burn the Chengdu firing with anti alkaline strong, but the strength is high, nearly doubled than clay brick life.

The industrial trials in Xinmi Changxing Refractories Co., and recommended for coke oven chamber wall three hot repair methods: flame spraying; ceramic welding using oxygen; theexothermic material (heating material) to repair. The process is: with the help of the principle of common heat generated to form a protective layer on the surface of masonry of refractory material to repair the surface.

Flame gunning method of flame gunning refractory products, powder particles melt in the liquid or gaseous fuel to the flame, and was sent to the surface to be repaired. The masonry is nozzle flame of heating, so using this method without special restrictions on the temperature, but also can be used to refractory powder cheaper to obtain high quality spraying layer. The principle of the ceramic welding method is added to the material of strong oxidant (exothermic material: aluminum, silicon etc.). Wind transport by means of oxygen jet flames, oxidant and refractory powder to the surface to be repaired.

The characteristics of refractory fiber

1 high temperature resistant.

The highest use temperature up to 1250~2500 degrees. The most commonly used asbestos is 

only 500~550 degrees, 580~830 degrees C and slag wool, aluminum silicate fiber reaches more than 1000 DEG C.

2 conductivity is low.

Refractory fiber under high temperature thermal conductivity is very low, such as 1000 DEG C, thermal conductivity of aluminum silicate fiber only for clay brick lightweight clay brick 20%, 38%.

3 small volume densities.

Generally 0.1~0.2g/cm fand, general clay brick lightweight clay brick for 1/20~1/10, 1/10~1/5. Therefore, the application of industrial furnace refractory fiber instead of refractory brick, the furnace body weight, wall thickness. Such as heating furnace lining is reduced by 80%, the furnace wall thickness of 50%.

4 good chemical stability.

In addition to alkali, fluoride, sulphate, almost not affected by chemical erosion.

5 good thermal shock resistances.

Regardless of the fiber material or product, all brick incomparable good thermal shock resistance.

6 low thermal capacity.

1/72 heat capacity of fiber material only light refractory brick, clay brick 1/42. Refractory lining in the afternoon to do, heat loss is small, fuel saving, fast temperature rise, the intermittent operation furnace was love.

7 soft, easy processing.

Can be made into a variety of products and shape of parts, construction is convenient, the labor intensity is low, the effect is good.

Methods to decrease the porosity rate of refractory brick

Production of refractory  brick  is always encountered too many holes, how can we reduce the occurrence of this situation? Today we shall all requirements to introduce how to reduce the rate of porosity of refractory brick.

Selection of high density, low water absorption rate of the raw material, through the reasonable distribution is the key to prepare low porosity refractory brick. Refractory brick is used 50% of the soft clay and 50% hard clay clinker ingredients, according to a certain size requirements, forming, drying, firing at high temperature of 1300~1400 DEG C under the. Refractory mineral is mainly composed of kaolinite (Al2O3 – 2SiO2 – 2H2O) and 6%~7% impurities (potassium, sodium, calcium, titanium, iron oxide). The sintering process is mainly kaolinite continuous dehydration decomposition of mullite (3Al2O3 – 2SiO2) crystallization process. Refractory brick in SiO2 and Al2O3 on the sintering of eutectic of low melting point of silicate and impurities in the formation process of mullite crystals surrounded by around. In the process of baking temperature control at 1350 to 1380 DEG C, appropriate to increase the low porosity clay brick firing temperature (1420 C), refractory brick contraction increased slightly, so that the refractory brick density increases slightly, and low porosity can be reduced.

Refractory materials mainly used what place

Refractory material is the basis of materials in the field of high temperature technology. Department of applied very widely. Which is the most widely used in a variety of thermalequipment and high temperature in the container as resistance to high temperature structural material and lining. In the iron and steel metallurgy industry, coke oven is mainly composed of refractory materials. BF and hot blast furnace iron making steelmaking furnace, heating furnace, soaking pit, are absolutely indispensable in accordance with requirements of various refractory material. Not only the liquid steel casting to consume a large amount of refractory material, casting more need some high quality  refractory materials. Refining outside the furnace refractories have superior species would not be able to achieve. The statistical results show that the iron and steel industry is the most need the Department refractory material, accounting for about 60% of the total output of refractory materials. Smelting and processing of non-ferrous metals is also inseparable from therefractory material. High temperature operation Department of building materials industry and other silicate products, such as all the high temperature furnace glass industry, cement industry, ceramic industry and its lining must be made of refractory material to build. Other such as chemical industry, power, machinery manufacturing and other industrial high temperature operations in a variety of baking furnace, sintering furnace, heating furnace, boiler and flue, a chimney, protective layer must be refractory material.

In short, when some structures, apparatus, equipment or containers, in more than 1000 high temperature operation, because there may be a physical, chemical and mechanical effects, the deformation and the softening and melting material, or erosion, erosion, collapse or damage phenomenon, not only can make the operation could not be sustained. The service interruption, affect the production of materials, processing and pollution, affecting the quality of the products; it must adopt the refractory material with resistance to high temperature.

Requirement for fireclay bricks acceptance

Acceptance of fireclay bricks masonry of refractory brick works, to carefully check the flue gas in the furnace at, in, particular attention should be paid to the single arch, vault, and the bottom of the equipment. Then I will give you detailed introduction:

1, in the building when the fire clay brick, refractory and mud, labeling, etc., composition and levels are required to comply with the specifications and drawings;

2, to ensure the quality of construction fire clay brick is good, also is to follow the wrong sewing, levelness and verticality, mortar joint thickness and size and drawings in accordance with standards;

3, in the process of acceptance of the furnace body, assigned for the shop assistant director must come from above, each part of the furnace body check, made several mortar joint thickness inspection, furnace body parts measured by the size of the acceptance certificate of admission, careful examination of many important structure of the furnace body. The building block.

The above is to introduce you to the acceptance of clay firebrick, for reference purposes only, hope to help you, if you need to purchase, please contact us!”http://www.chinafirebrick.com”

Main factors affecting the service life of the refractory bricks

According to the long-term use of refractory bricks and refractory brick life mainly includes the influence of the specific use of the environment, the operating temperature of refractory brick
kiln, the use of the number of fly ash erosion. The principle of damage of refractory brick includes three aspects, the solubility, permeability, cinder of refractory brick erosion, friction. These three processes and ultimately affect the service life of the refractory brick, firebrick damage caused by.

Slag brick permeability leads to uneven texture, when encountered high temperature refractory bricks, due to uneven texture, resulting in heat coefficient is not the same, cracking caused by refractory brick. According to the summary of practical application, start and stop times increase the erosion of furnace firebrick, so the reasonable control of furnace of the open stop times can prolong the service life of refractory bricks.

Effect of fly ash on properties of  refractory brick is relatively large, very permeable brick composition of fly ash is silica, a relatively high calcium oxide, if these two components in coal ash, so the erosion of refractory brick is very large, a reasonable construction of the two components can reduce the erosion of refractory bricks to improve refractory brick service life.